[PATCH 4/6] fs/epoll: robustify ep->mtx held checks

[Davidlohr Bueso]

Insted of just commenting how important it is, lets make
it more robust and add a lockdep_assert_held() call.

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---
 fs/eventpoll.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 347da3f4f5d3..6a0c2591e57e 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1637,6 +1637,8 @@ static __poll_t ep_send_events_proc(struct eventpoll *ep, struct list_head *head
 	 * Items cannot vanish during the loop because ep_scan_ready_list() is
 	 * holding "mtx" during this call.
 	 */
+	lockdep_assert_held(&ep->mtx);
+
 	list_for_each_entry_safe(epi, tmp, head, rdllink) {
 		if (esed->res >= esed->maxevents)
 			break;
-- 
2.16.4